Copper: Evaluation of the Nutritional Status of Oil Palm Cultivated in the Eastern Amazon.

Oil palm is the main palm tree cultivated in the tropics, but little is understood about copper (cu) management in this crop. The objective of this study was to evaluate the nutritional status of copper in oil palms plants in the Eastern Amazon. The experiment was carried out in Tailândia, in the state of Pará (Brazil), using a completely randomized experimental design, with four replications and seven treatments (ages of oil palm plants: 2, 3, 4, 5, 6, 7, and 8 years). The concentration, accumulation, cycling, immobilization, export, and efficiency of copper use in the different organs of the plants were evaluated. The highest copper concentrations occurred in the palm heart in the second year, and copper accumulation (481 g ha−1) and export were highest in the eighth year of growth. Among the plant organs, the highest copper exports occurred in the bunches (69.38 g ha1). The highest proportion of copper was immobilized (326 g ha−1), while the lowest proportion of the nutrient accumulated in the export organs. Copper use efficiency increased with plant age, and efficiency was greater in the petiole and lower in the palm heart. The copper requirement increased with the age of oil palms grown in the Eastern Amazon. [ABSTRACT FROM AUTHOR]